This invention pertains to a process for making saturated aliphatic aldehydes from diesters of carbonic acid and particularly to the reaction of diesters of carbonic acid with synthesis gas in the presence of a rhodium or cobalt catalyst or other Group VIII transition metal.
Much research work has been done on the conversion of synthesis gas, that is, mixtures of carbon monoxide and hydrogen, into low molecular weight organic compounds. For example, methanol has been made from synthesis gas and then further reacted with synthesis gas by hydroformylation, homologation, or carbonylation to provide acetaldehyde, ethanol and acetic acid, respectively. These reactions are catalyzed by one or more transition metals of Group VIII of the Periodic Table. In these reactions a halogen, as for example, iodine, or halogen containing compounds, for example, methyl iodide, must be utilized in conjunction with the metal catalyst in order for a reaction to be carried out at commercially acceptable rates and selectivities.
It is therefor an object of this invention to provide a process which utilizes synthesis gas and products linear aldehydes at high conversion rates and selectivities under relatively mild reaction conditions.
It is another object of this invention to provide a process for producing linear aldehydes via synthesis gas with a minimum of loss of the starting materials, that is, with high conversions of starting materials to the desired aldehydes.
Other objects will become apparent to those skilled in the art upon a reading of the specifications.